[Coco] Emulating a 1980 4K CoCo on PC

Arthur Flexser flexser at fiu.edu
Wed Dec 31 18:01:56 EST 2014


Kip, a simple CLEAR 200,4096 (or maybe 4095) after startup should be all
you need to have the equivalent of a 4K CoCo if you've removed the Extended
Basic ROM.

Art

On Wed, Dec 31, 2014 at 5:50 PM, <computerdoc at sc.rr.com> wrote:

> Hi Early 4K Coco 1 Enthusiasts,
> I must say I am quite impressed with how many of you guys actually started
> their journey with the Coco with the very first Coco!  When the Coco 1
> first appeared with a $500 price tag, if memory serves, it was a bit too
> high for me.  In the '81 to '83 time frame the Coco 1 with 64K was about
> $200 which was when I got in on the Coco journey myself.  Although I
> started with Color Basic v? in my Coco 1, I had 64K so I never experienced
> all the limitations a 4K Coco would pose.  I did know what it was like to
> use the all popular unreliable Cassette Recorder for Basic Program
> storage.  I spent hours at a time working hard to make sure my programs
> stored correctly many times by recording them more than once.  Did anyone
> else do that too?
> When I saw this 4K Coco 1 Color Basic Contest, I thought it would be both
> fun and frustrating to write a Basic program on a 4K Coco 1, so I finally
> got XRoar running with just 4K of ram and just Color Basic 1.2 with quite a
> bit of effort.  I tried over and over trying to get the xroar.conf file to
> recognize my 4K Coco configuration which by the way it never did, so I
> moved all the extbas11.rom, disk11.rom and hdbdw3bck.rom image files to a
> subdirectory called "hide stuff" and put the command line parameter "-ram
> 4" for xroar.exe into the icon properties on my Windows 7 laptop and as if
> by magic XRoar started up with a 4K Coco 1 running Color Basic.  Of course
> all the machines in XRoar are now 4K!  :)
> I have also had to restart writing my Basic program for the contest
> several times as it seems that XRoar exits quite abruptly if you press
> <CTRL>-C with no prompt for "Are you sure?"!  It is beginning to get a bit
> aggravating since I have Asperger's Syndrome, ADD, Bipolar Disorder and
> OCD!  ARGH!  There is quite a bit going on in my head!  How about yours?
> Anyway, I'm thinking of using a real Coco 1 and try poking the top-of-ram
> location in low ram for Color Basic to $0FFF and see was happens.  I need
> to look at my Color Basic Unraveled pdf file to get that address though.  I
> wonder if poking that address, poking 113 with 0 and exec &hA027 will give
> me a 4K Coco 1?  Of course I will pull out the 24 pin Extended Basic eprom
> and pull out my cassette recorder again after decades and see what
> happens.  It will be anything but dull.  Now that I have proofread this
> email, poking the top-of-ram may not work.  If not, I may have to modify
> the Color Basic code to only have 4K of ram.  I'll let you guys know how
> this goes.
> I'm on vacation right now, so I won't be able to test all this out until I
> get back home this Saturday.  If any of you are in the Myrtle Beach Area or
> close by, I'd like to meet you.  Take care my friends.
>
> Kip Koon
> computerdoc at sc.rr.com
> http://www.cocopedia.com/wiki/index.php/Kip_Koon
>
>
>
> --
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>


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